Changes in lymphocyte HSP70 levels in women handball players throughout 1 year of training: the role of estrogen levels.

Heat shock protein 70 (HSP70) is a chaperone that maintains protein conformation during heat stress. It has recently been observed that HSP70 may be released from cells in response to increased energy demand (e.g., exercise) and/or oxidative stress. Since HSP70 levels should change in response to athletic training, we have investigated whether blood HSP70 levels in young women handball players change over a complete training season. Thirty women handball players (12-24 years old) were divided into low (≥30 pg mL(-1)) (LE) and normal (30-330 pg mL(-1)) (NE) estradiol groups. HSP70 levels in lymphocytes and plasma and blood redox parameters were evaluated over 1 year (2009), with sampling at the beginning, middle, and end of the season. We observed no changes in superoxide dismutase activity or protein carbonyl or extracellular HSP70 levels, while catalase activity increased at the middle of the season in the NE group, and the thiobarbituric acid species levels in both groups were higher at the beginning of the season than at the middle or end. The lymphocyte HSP70 content was higher at the middle and end than at the beginning of the season in the NE group and also higher in the LE group than in the NE group at the beginning of the season. These results suggest that plasma estradiol levels may play an important role in exercise training and that the intracellular HSP70 content, a biomarker for inflammation, is affected by both estradiol levels and exercise-induced oxidative stress.

The effects of vitamin A supplementation to rats during gestation and lactation upon redox parameters: increased oxidative stress and redox modulation in mothers and their offspring.

Vitamin A is an essential nutrient required in adequate amounts for reproduction and development. Subtle variations in the status of maternal nutrition may affect physiological and metabolic parameters in the fetus. Evidence suggests a key role for oxidative stress in these events. Literature is controversial about the effects of vitamin A supplementation. Here, we studied the effects of vitamin A supplementation on female Wistar rats during gestation and lactation on oxidative stress parameters of maternal and offspring tissues. Rats received daily doses of vitamin A at 2500, 12,500 and 25,000IU/kg. We observed an increase of oxidative damage markers in the reproductive tissues and plasma of dams. The activity of glutathione-S-transferase was modulated by vitamin A supplementation. It was found to be increased in the liver of dams and decreased in the kidneys of mothers and offspring. In pups, supplementation decreased the total antioxidant potential of the liver along with decreased superoxide dismutase/catalase activity ratio in the kidney. The levels of lipoperoxidation were increased in male offspring, but decreased in female pups. Collectively, the results suggest that excessive vitamin A intake during gestation and lactation might be toxic for mothers with adverse effects for the developing offspring.